^ yup, although I'm going to assume cocker, as Nelson's have them built-in, in which case just get the ccm autotrigger kit. From my understanding making the autotrigger itself isn't hard (and I couldn't imagine it being difficult, I could probably make one by hand) but god have mercy on your soul if you try and drill into the side of a pump rod.

Isn't the hammer a Nelson? (haven't seen the internals yet, just assuming) but if that's the case then ALL Nelson's are inherently designed with an a/t into them....so it's not as though kingman went out and added an autotrigger into the gun.